JP6699485B2 - Voltage detector - Google Patents

Description

  The present invention relates to a voltage detection device applied to an assembled battery including a series connection body of a plurality of battery cells.

  BACKGROUND ART Conventionally, as disclosed in, for example, Patent Document 1 below, a voltage detection device that detects a terminal voltage of a battery cell that constitutes an assembled battery is known. An assembled battery that is a voltage detection target of this voltage detection device includes a plurality of detection blocks that are serially connected bodies of at least two battery cells.

  The voltage detection device includes a monitoring unit that detects the state of the battery pack, and a control unit that is provided separately from the monitoring unit and that receives the detection result of the monitoring unit. The monitoring unit includes a main voltage detection unit that detects, for example, a terminal voltage of each battery cell in the detection block. The control unit performs charging/discharging control of the battery cells based on the input voltage detection result.

  The control unit further includes a sub-voltage detection unit that detects the terminal voltage of the detection block. The sub-voltage detection unit is provided to make the configuration for detecting the voltage redundant from the viewpoint of ensuring the functional safety of the voltage detection device. The control unit determines whether or not there is an abnormality in the assembled battery based on the voltage detection result of the sub voltage detection unit.

JP, 2014-107979, A

  The voltage detection device includes an electric path connected to each of the positive electrode side and the negative electrode side of the detection block, and a switch provided in each electric path. The control unit selects, from the plurality of detection blocks, a detection block whose terminal voltage is to be detected. The control unit commands a closing operation of switches provided in the pair of electric paths connected to the selected detection block. Then, in the state where the switch is operated to be closed, the sub voltage detection unit detects the terminal voltage of the detection block via the pair of electric paths.

  A pair of electric paths for voltage detection is provided for each detection block. These electric paths are connected to the sub-voltage detection section via a voltage input section provided in the control section. Here, considering that the main body that outputs the switch operation command is the control unit, a configuration in which the switch is provided in the control unit is conceivable. In this case, the number of voltage input units provided in the control unit is the same as the number of electric paths. However, in this configuration, if the number of detection blocks changes due to a change in the specifications of the battery pack, the number of voltage input units also changes. As a result, it is necessary to change the shape of the control unit. This is not preferable from the viewpoint of sharing parts.

  An object of the present invention is to provide a voltage detection device which is applied to an assembled battery and can share parts.

  1st invention is a voltage detection apparatus applied to the assembled battery (10) provided with the series connection body of several battery cell (10a-10d), The monitoring part (MD1-MDn) which detects the state of the said assembled battery. And a control unit (20) provided with the detection result of the monitoring unit and provided separately from the monitoring unit. In the first invention, at least two of the battery cells forming the assembled battery are connected in series as a detection block (BM1 to BMn), and the battery cells forming the detection block are connected in series. Each or each of the detection blocks has a number of battery cells connected in series smaller than the number of battery cells forming the detection block as a detection target battery. The monitoring unit, as a state of the assembled battery, a main voltage detection unit (30) that detects a terminal voltage of each of the detection target batteries, and a positive electrode side input unit (electrically connected to the positive electrode side of the detection block). Ci5), the negative electrode side input part (Ci1) electrically connected to the negative electrode side of the detection block, and the positive electrode side input part and the negative electrode side input part, as the state of the assembled battery, the detection And a sub-voltage detector (40a, 40b, 41, 42) for detecting the terminal voltage of the block.

  In the first invention, the monitoring unit includes a main voltage detection unit, a positive electrode side input unit electrically connected to the positive electrode side of the detection block, and a positive electrode side input unit electrically connected to the positive electrode side of the detection block. And have. Further, the monitoring unit further includes a sub-voltage detection unit that detects the terminal voltage of the detection block via the positive side input unit and the negative side input unit.

  Since the sub-voltage detection unit is provided in the monitoring unit, in a configuration in which a plurality of detection blocks are provided, the number of voltage input units for electrically connecting the detection blocks and the control unit to the control units is the same as the number of control units. There is no need to provide it. Therefore, even if the number of detection blocks changes due to a change in the specification of the battery pack, it is possible to share a control unit that constitutes the voltage detection device.

  In the second invention, the main voltage detection unit constitutes a monitoring IC (60) which is a flat rectangular parallelepiped integrated circuit in the thickness direction, and at least a part of the sub-voltage detection unit is A redundant IC (70) which is a flat rectangular parallelepiped in the vertical direction and which is an integrated circuit separate from the monitoring IC is formed, and the thickness direction of the monitoring IC is defined as the normal direction. One of the two outer surfaces is a monitoring back side (60a) and the other is a monitoring front side (60b). In the redundant IC, two thicknesses are set as normal directions. One of the outer surfaces is a redundant back surface (70a) and the other surface is a redundant front surface (70b), and the area of the monitoring front surface is equal to or larger than the area of the redundant back surface. When the monitoring IC is viewed from the side of the monitoring surface, the redundant back side is mechanically connected to the side of the monitoring surface with the contour of the redundant IC not protruding from the contour of the monitoring IC. ing.

  In the second aspect of the invention, the main voltage detecting section constitutes a monitoring IC which is an integrated circuit having a flat rectangular parallelepiped shape in the thickness direction. Further, at least a part of the sub-voltage detection section forms a rectangular parallelepiped shape that is flat in the thickness direction, and configures a redundant IC that is an integrated circuit different from the monitoring IC. Note that the terms “monitoring” and “redundancy” attached to each IC simply distinguish between an IC including a main voltage detection unit and an IC including at least a part of the sub voltage detection unit. It is for.

  While the voltage detection target of the sub voltage detection unit is the detection block, the voltage detection target of the main voltage detection unit is the number of battery cells that is smaller than the number of battery cells that configure the detection block. Therefore, the voltage detection accuracy required for the main voltage detection unit is higher than the voltage detection accuracy required for the sub voltage detection unit.

  Here, the stress may be applied to the monitoring IC including the main voltage detection unit, so that the monitoring IC may be distorted. Examples of factors that cause stress include heat stress. Examples of the heat stress include heat stress at the time of reflow when the monitor IC is attached to the monitor, or heat stress due to a temperature change of the environment surrounding the monitor IC. When the monitoring IC is distorted, the voltage detection accuracy of the main voltage detection unit forming the monitoring IC may be reduced.

  Therefore, in the second invention, the area of the monitoring front surface of the monitoring IC is set to be larger than the area of the redundant back surface of the redundant IC. Then, when the monitoring IC is viewed from the side of the monitoring surface, the redundant back side is mechanically connected to the side of the monitoring surface with the contour of the redundant IC not protruding from the contour of the monitoring IC. Therefore, even if stress is applied to the monitoring IC, the redundant IC can prevent the monitoring IC from being distorted. As a result, it is possible to prevent a decrease in the voltage detection accuracy of the main voltage detection unit that constitutes the monitoring IC.

  In addition, according to the second aspect of the invention, since the redundant IC is provided on the side of the monitoring table of the monitoring IC, the mounting area of each detection unit required when the main voltage detection unit and the sub voltage detection unit are provided in the monitoring unit is reduced. it can. As a result, the monitoring unit can be downsized.

  Instead of the second invention, for example, as in the fourth invention, a configuration is adopted in which the monitoring IC and the redundant IC are arranged side by side in a plan view of the monitoring IC and the redundant IC. You can also do it.

  A third aspect of the invention includes a lead frame (80) on which the monitoring IC is mounted from the back side surface of the monitoring and which has a plurality of leads (80c1) in the periphery. In the third invention, the area of the monitoring surface side is made larger than the area of the redundant back surface, and the monitoring IC is one of the monitoring table side surfaces when the monitoring IC is viewed from the monitoring table side surface. A plurality of electrode pads (61) are formed along one side of the monitoring front surface in a region that does not overlap with the redundant IC, and the redundant IC is formed on the redundant front surface along one side of the redundant front surface. A plurality of electrode pads (71) are formed, and the redundant back side is the monitoring table in a state where the electrode pad of the redundant IC and the electrode pad of the monitoring IC face the same direction or substantially the same direction. One of the electrode pads of the redundant IC and one of the electrode pads of the monitoring IC are mechanically connected to the side surface, and each of the one of the electrode pads of the monitoring IC is commonly used by the monitoring IC and the redundant IC among the plurality of leads. It is electrically connected to the leads to be used by bonding wires (90, 91).

  There is a configuration in which one of the electrode pads of the redundant IC and one of the electrode pads of the monitoring IC are connected to one of a plurality of leads that is commonly used by the monitoring IC and the redundant IC. In this configuration, when the monitoring IC is viewed from the monitoring surface side and the distance between the redundant surface side electrode pad and the commonly used lead is long, the commonly used lead and the redundant surface side electrode pad are long. There is a risk that the bonding wire connecting to and will be cut. In order to avoid this problem, a relay electrode pad is formed on the monitoring surface side of the monitoring IC, the electrode pad on the redundant surface side and the relay electrode pad are connected by a bonding wire, and at the same time as the relay electrode pad. It is also conceivable to adopt a configuration in which leads commonly used are connected by bonding wires. However, in this configuration, it is necessary to additionally form an electrode pad for relay in the monitoring IC. Also, with this configuration, the number of operations for connecting with the bonding wire increases.

  Therefore, in the third invention, the area of the monitoring surface side is made larger than the area of the redundant back surface, and when the monitoring IC is viewed from the monitoring surface side, the area of the monitoring table side that does not overlap with the redundant IC is monitored. A plurality of electrode pads are formed along one side of the front side surface. In addition, a plurality of electrode pads are formed on the redundant front surface along one side of the redundant front surface. The redundant back side surface is mechanically connected to the monitoring front side surface in a state where the electrode pad of the redundant IC and the electrode pad of the monitoring IC face the same direction or substantially the same direction.

  According to the third invention, when the monitoring IC is viewed from the side of the monitoring surface, the distance between the electrode pad on the redundant surface and the lead commonly used can be shortened. Therefore, one of the electrode pads of the redundant IC and one of the electrode pads of the monitoring IC can be directly connected to the commonly used lead by the bonding wire. As a result, it is not necessary to form relay electrode pads on the monitoring IC, and the number of electrode pads formed on the monitoring IC can be reduced. In addition, it is possible to prevent an increase in the number of operations for connecting with the bonding wire.

  In the fifth invention, the number of the detection blocks is plural, the monitoring section is provided individually corresponding to each of the detection blocks, and the sub-voltage detection section is configured to detect the terminal voltage of the detection block. Voltage dividing resistors (40a, 40b) for dividing the voltage, a reference power source (42) for outputting a reference voltage for detecting the charge state of the detection block, an inverting input terminal and a non-inverting terminal A comparator (41) including an input terminal, wherein the voltage divided by the voltage dividing resistor is input to one terminal of the inverting input terminal and the non-inverting input terminal, and the reference voltage is input to the other terminal. ), and have. A fifth aspect of the present invention includes a DC power supply (50) and a resistor (52) whose first end side is connected to the DC power supply. In the fifth invention, the monitoring unit is closed or opened in accordance with the logic of the output voltage of the signal output unit (Ca) and the output terminal of the comparator, and the signal output unit and the ground are electrically connected. And a communication switch (45) that is a switch that is electrically connected, the second end side of the resistor is electrically connected to the signal output unit of each monitoring unit, and the control unit Has a signal input portion (Cb) electrically connected to the second end side of the resistor.

  In the fifth invention, the monitoring section has a signal output section and a communication switch. A fifth aspect of the invention includes a DC power supply and a resistor whose first end side is connected to the DC power supply. A signal input unit included in the control unit is electrically connected to the second end side of the resistor. According to this configuration, even if the number of detection blocks changes due to a change in the specification of the battery pack, it is not necessary to change the number of signal input units of the control unit. Therefore, even if the specifications of the battery pack change, it is possible to share the control unit that constitutes the voltage detection device.

  In the fifth invention, the sub-voltage detector includes a voltage dividing resistor, a reference power supply, and a comparator. According to this configuration, the voltage divided by the voltage dividing resistor crosses the reference voltage for detecting the charge state of the detection block, so that the logical value of the output voltage of the output terminal of the comparator is inverted.

  When the logical value of the output voltage of the output terminal of the comparator is determined, the operation state of the communication switch that electrically connects the signal output unit and the ground is switched from one of the closed state and the open state to the other state. .. According to this configuration, when the logic of the output voltage of the output terminal of at least one of the monitoring units is inverted, the logic of the input signal of the signal input unit electrically connected to the second end side of the resistor is changed. Invert. Therefore, the control unit can determine the state of charge of the detection block based on the input signal of the signal input unit.

  Here, the voltage detection device can perform a diagnostic process of a communication system from the reference power source or the comparator to the signal input unit via the communication switch and the signal output unit. Specifically, for example, as in the sixth invention, the voltage generation unit (46) that generates and outputs the diagnostic voltage, and the detection block and the voltage dividing resistor by being in the closed state. A first switch (SW1) that electrically connects the two and electrically disconnects the detection block from the voltage dividing resistor by being opened, and a closed state by the first switch (SW1). Between the non-inverting input terminal and the inverting input terminal of the comparator, the voltage dividing input terminal, which is the terminal to which the voltage divided by the voltage dividing resistor is input, and the voltage generator are electrically connected. And a second switch (SW1) that electrically disconnects the voltage dividing input terminal and the voltage generating unit by being electrically connected and opened. In a sixth aspect, the control unit changes the diagnostic voltage so as to cross the reference voltage with the first switch in an open state and the second switch in a closed state. When it is determined that the logic of the input signal of the signal input unit is reversed when the diagnostic voltage is changed and the process of operating the voltage generating unit is performed, it is determined that no abnormality has occurred in the reference power supply. When it is determined that the logic of the input signal of the signal input unit is not inverted when the diagnostic voltage is changed, a process of determining that an abnormality has occurred in the reference power supply, Can be adopted.

  As a configuration for performing the diagnostic process, for example, as in the seventh invention, the control unit is in a state in which the first switch is in the open state and the second switch is in the closed state. In the process of operating the voltage generator to make the diagnostic voltage smaller than the reference voltage or to make the diagnostic voltage higher than the reference voltage, the diagnostic voltage is smaller than the reference voltage. If there is a failure or if the diagnostic voltage is higher than the reference voltage, based on the logic of the input signal of the signal input unit, a process of diagnosing the presence or absence of an abnormality in the communication system is adopted. can do.

  Incidentally, for example, as in the eighth aspect of the invention, a configuration in which the voltage generation section is provided in the main voltage detection section can be adopted. According to this configuration, the voltage generation unit provided in the main voltage detection unit can be used for the abnormality diagnosis of the reference power supply and the communication system, and the increase of the circuit for the diagnosis can be prevented.

1 is an overall configuration diagram of a power supply system according to a first embodiment. Sectional drawing of a semiconductor module. The top view of a part of structure of a semiconductor module. The top view of a part of composition of the semiconductor module concerning related technology. 6 is a flowchart showing a procedure of a diagnosis process according to the first embodiment. The flowchart which shows the procedure of a diagnostic process. The whole block diagram of the power supply system which concerns on 2nd Embodiment. The top view of a part of composition of the semiconductor module concerning other embodiments.

(First embodiment)
Hereinafter, a first embodiment that embodies a voltage detection device according to the present invention will be described with reference to the drawings. The voltage detection device according to the present invention is applied to a power supply system mounted in, for example, a hybrid vehicle or an electric vehicle.

  As shown in FIG. 1, the power supply system includes an assembled battery 10. The assembled battery 10 serves as a power supply source of an in-vehicle electric load including a running motor (not shown) of the vehicle. The assembled battery 10 includes a series connection body of battery cells as single cells, and has an inter-terminal voltage of, for example, several hundreds V. A storage battery such as a lithium-ion battery can be used as the battery cell.

  In the present embodiment, a battery module as a detection block is configured by integrating at least two battery cells connected in series among the battery cells configuring the assembled battery 10. In the present embodiment, a series connection body of four battery cells 10a to 10d is configured as a battery module. Further, the battery pack 10 is configured by a series connection body of n battery modules. In the present embodiment, the assembled battery 10 is assumed to have a configuration in which n is an integer of 3 or more. In the present embodiment, among the battery modules forming the assembled battery 10, the first battery module BM1, the second battery module BM2,..., The n-1th battery module BMn-1, in order from the low potential side battery module. It will be referred to as an nth battery module BMn.

  The voltage detection device includes first to nth monitoring units MD1 to MDn and a control unit 20. The monitoring units MD1 to MDn and the battery modules BM1 to BMn are individually provided.

  Here, m is defined as an integer of 1 to n-1. The positive electrode side of the mth battery module BMm and the negative electrode side of the m+1th battery module BMm+1 adjacent to the high potential side of the battery module BMm are electrically connected by the mth conductive member Wm. In the present embodiment, the mth conductive member Wm is a wire as a conductive member.

  Subsequently, the first to nth monitoring units MD1 to MDn will be described. In this embodiment, the monitoring units MD1 to MDn have the same configuration. Therefore, the configuration of the monitoring unit will be described by taking the nth monitoring unit MDn as an example. Further, in FIG. 1, the reference numerals of the respective members forming the monitoring unit are common to the monitoring units MD1 to MDn for convenience sake.

  The nth monitoring unit MDn includes a circuit board, and the circuit board is provided with the first to fifth battery input units Ci1 to Ci5. The first to fifth battery input units Ci1 to Ci5 are configured as terminals. In the present embodiment, the first battery input unit Ci1 corresponds to the “negative electrode side input unit” and the fifth battery input unit Ci5 corresponds to the “positive electrode side input unit”.

  The nth monitoring unit MDn includes a high potential electrical path LHM having a first end electrically connected to the fifth battery input unit Ci5. In addition, the n-th monitoring unit MDn has a first end electrically connected to the first battery input unit Ci1 and a second end electrically connected to the second end of the high potential electrical path LHM. A potential electric path LLM is provided.

  The negative electrode side of the nth battery module BMn is connected to the first battery input section Ci1 via the first input path L1, and the second battery input section Ci2 is connected to the first battery cell 10a via the second input path L2. The positive electrode side and the negative electrode side of the second battery cell 10b are connected. The positive electrode side of the second battery cell 10b and the negative electrode side of the third battery cell 10c are respectively connected to the third battery input section Ci3 via the third input path L3, and the fourth battery input section Ci4 is connected to the fourth input side. The positive electrode side of the third battery cell 10c and the negative electrode side of the fourth battery cell 10d are connected to each other via the path L4. The positive electrode side of the nth battery module BMn is connected to the fifth battery input unit Ci5 via the fifth input path L5.

  In addition, each of the input paths L1 to L5 may be integrated as a harness member while being electrically insulated from each other.

  The nth monitor MDn includes a main voltage detector 30. The main voltage detection unit 30 has a function of individually detecting the terminal voltages of the battery cells 10a to 10d forming the nth battery module BMn. That is, in this embodiment, each battery cell is a “detection target battery”. The main voltage detection unit 30 detects the terminal voltage of the first battery cell 10a via the first input path L1 and the second input path L2, and the second battery via the second input path L2 and the third input path L3. The terminal voltage of the cell 10b is detected. Further, the main voltage detection unit 30 detects the terminal voltage of the third battery cell 10c via the third input path L3 and the fourth input path L4, and detects the terminal voltage via the fourth input path L4 and the fifth input path L5. 4 The terminal voltage of the battery cell 10d is detected. The main voltage detection unit 30 includes an AD converter and converts the detected terminal voltage from analog data into digital data.

  In the nth monitoring unit MDn, the high potential electric path LHM is provided with the first switch SW1. In this embodiment, the first switch SW1 is opened and closed by the main voltage detection unit 30. In the present embodiment, the first switch SW1 is a normally open semiconductor switching element. A relay, for example, may be used as the first switch SW1.

  In addition, in the high-potential electrical path LHM, a low-pass filter including a resistor and a capacitor may be provided closer to the fifth battery input section Ci5 than the first switch SW1.

  In the high-potential electrical path LHM, a first voltage dividing resistor 40a is provided on the side opposite to the fifth battery input section Ci5 with the first switch SW1 interposed therebetween. The second potential dividing resistor 40b is provided in the low-potential electrical path LL. One end of the first voltage dividing resistor 40a and one end of the second voltage dividing resistor 40b are electrically connected.

  The nth monitoring unit MDn has a function of detecting the state of charge of the nth battery module BMn. In the present embodiment, the nth monitoring unit MDn has a function of detecting whether or not it is in an overcharged state. In order to realize this function, the nth monitoring unit MDn includes a comparator 41 and a reference power supply 42 that is a DC power supply. The reference power supply 42 is connected to the non-inverting input terminal of the comparator 41, and the connection point of the first voltage dividing resistor 40a and the second voltage dividing resistor 40b is connected to the inverting input terminal of the comparator 41.

  The reference voltage VREF, which is the output voltage of the reference power supply 42, is set to a value capable of determining that the nth battery module BMn is in the overcharged state. Specifically, for example, the reference voltage VREF may be set to a value corresponding to the allowable upper limit value of the terminal voltage of the nth battery module BMn. More specifically, for example, the reference voltage VREF may be set to a value obtained by dividing the allowable upper limit value by the first and second resistors 40a and 40b for voltage division.

  In the present embodiment, the first voltage dividing resistor 40a, the second voltage dividing resistor 40b, the comparator 41, and the reference power source 42 form a "sub-voltage detector".

  The nth monitoring unit MDn includes a communication power supply 43 which is a DC power supply, a communication resistor 44, and a photocoupler 45 as a “communication switch”. The communication power source 43 is connected to the first end of the communication resistor 44, and the anode of the photodiode forming the photocoupler 45 is connected to the second end of the communication resistor 44. The output terminal of the comparator 41 is connected to the cathode of the photodiode.

  The collector of the phototransistor forming the photocoupler 45 is connected to the signal output unit Ca of the nth monitoring unit MDn, and the emitter of the phototransistor is connected to the ground of the power supply system. In the present embodiment, the signal output unit Ca is configured as a terminal.

  The nth monitoring unit MDn includes a DA converter 46 corresponding to a “voltage generating unit” and a second switch SW2 provided on an electric path connecting the DA converter 46 and the inverting input terminal of the comparator 41. There is. In the present embodiment, the second switch SW2 is opened/closed by the main voltage detection unit 30. In the present embodiment, the second switch SW2 is a normally open semiconductor switching element. A relay, for example, may be used as the second switch SW2. In the present embodiment, the DA converter 46 is used, for example, to correct the voltage detected by the main voltage detection unit 30.

  In the present embodiment, the main voltage detection unit 30, the first switch SW1, the first voltage dividing resistor 40a, the second voltage dividing resistor 40b, the DA converter 46 and the second switch SW2 are one integrated circuit. It is configured as an IC 60. Further, in this embodiment, the comparator 41 and the reference power supply 42 are configured as a redundant IC 70 which is one integrated circuit. The redundant IC 70 is configured on a chip different from the monitoring IC 60.

  The monitoring IC 60 and the redundant IC 70 will be described with reference to FIGS. 2 and 3.

  As illustrated, each of the monitoring IC 60 and the redundant IC 70 has a flat rectangular parallelepiped shape in the thickness direction. In the monitoring IC 60, one of the two outer surfaces whose normal direction is the thickness direction is a monitoring back side surface 60a, and the other is a monitoring front side surface 60b. In the redundant IC 70, one of the two outer surfaces whose normal direction is the thickness direction is a redundant back side surface 70a, and the other is a redundant front side surface 70b.

  The area of the monitoring front side surface 60b is made larger than the area of the redundant back side surface 70a. Further, in the present embodiment, the monitoring front side surface 60b and the redundant back side surface 70a are flat surfaces having no unevenness. In this configuration, the redundant IC 70 is attached to the central portion of the monitoring IC 60 with the entire surface of the redundant back surface 70a being in contact with the monitoring front surface 60b. The redundant IC 70 may be mechanically connected to the monitoring IC 60 by applying an adhesive between the redundant back surface 70a and the monitoring front surface 60b.

  The redundant IC 70 is attached to the monitoring IC 60 in a state in which the entire surface of the redundant back side surface 70a is in contact with the monitoring front side surface 60b, so that the deterioration of the voltage detection accuracy of the main voltage detection unit 30 forming the monitoring IC 60 is prevented. This is because

  That is, the voltage detection target of the sub-voltage detection unit including the first voltage dividing resistor 40a, the second voltage dividing resistor 40b, the comparator 41, and the reference power supply 42 is the detection block, whereas the voltage of the main voltage detecting unit 30 is The detection target is each of the battery cells 10a to 10d. Therefore, the voltage detection accuracy required for the main voltage detection unit 30 is higher than the voltage detection accuracy required for the sub voltage detection unit. Here, due to the stress acting on the monitoring IC 60, the monitoring IC 60 may be distorted. When the monitoring IC 60 is distorted, the voltage detection accuracy of the main voltage detection unit 30 included in the monitoring IC 60 may decrease.

  Therefore, the redundant IC 70 is attached to the monitoring IC 60 with the entire surface of the redundant back surface 70a being in contact with the monitoring front surface 60b. As a result, even if stress is applied to the monitoring IC 60, the redundant IC 70 can prevent the monitoring IC 60 from being distorted. As a result, it is possible to prevent a decrease in voltage detection accuracy of the main voltage detection unit 30 included in the monitoring IC 60.

  In the present embodiment, the monitoring front side surface 60b and the redundant back side surface 70a are flat surfaces having no unevenness, but the present invention is not limited to this. For example, an uneven portion may be formed on at least one of a part of the monitoring front side surface 60b overlapping the redundant IC 70 and a part of the redundant back side surface 70a. In this case, when the monitoring IC 60 is viewed from the monitoring front side 60b, the redundant back side 70a is attached to the monitoring front side 60b with an adhesive or the like in a state where the outline of the redundant IC 70 does not protrude from the outline of the monitoring IC 60. Adopt a configuration. Also with this configuration, the distortion of the monitoring IC 60 can be suppressed.

  In the present embodiment, the monitoring IC 60 and the redundant IC 70 are packaged together with the lead frame 80 and the bonding wire with the mold resin 100 that is a sealing material to form a semiconductor module. The mold resin 100 is made of an electrically insulating synthetic resin material and is, for example, an epoxy resin.

  The lead frame 80 is a plate-shaped member made of a conductive material, and includes a die pad 80a, suspension leads 80b, and leads 80c. The die pad 80a is located in the center of the lead frame 80 and has a rectangular shape. The suspension leads 80b are four members that extend outward from the die pad 80a on the diagonals thereof. The lead 80c is an elongated member that extends toward the center of the die pad 80a, and a plurality of leads 80c are provided along the periphery of the die pad 80a between adjacent suspension leads 80b.

  The lead 80c is composed of an inner lead 80c1 located inside the mold resin 100 and an outer lead 80c2 exposed from the mold resin 100. The inner lead 80c1 extends in a direction parallel to the extending direction of the die pad 80a. The outer lead 80c2 is bent downward, and its tip portion extends in a direction parallel to the extending direction of the inner lead 80c1.

  When the monitoring IC 60 is viewed from the monitoring surface 60b, a plurality of electrode pads are formed along each side of the monitoring surface 60b in a region of the monitoring surface 60b that does not overlap the redundant IC 70. FIG. 3 shows a plurality of electrode pads 61 formed along a specific one of the four sides of the monitoring surface side 60b. In the present embodiment, a plurality of electrode pads 61 formed along the specific side include a power supply terminal that supplies power to the monitoring IC 60. On the other hand, on the redundant front surface 70b of the redundant IC 70, a plurality of electrode pads 71 are formed along one side of the redundant front surface 70b. In the present embodiment, a plurality of electrode pads 71 formed along this specific side include a power supply terminal that supplies power to the redundant IC 70. Further, in the present embodiment, the redundant IC 70 is attached to the monitoring IC 60 with the electrode pad 71 of the redundant IC 70 and the electrode pad 71 of the monitoring IC 60 facing in the same direction or substantially the same direction with reference to the central portion of the redundant IC 70. Has been.

  In the present embodiment, among the inner leads 80c1 arranged along each side of the die pad 80a, one of the inner leads 80c1 in the direction facing the electrode pads 61, 71 is commonly used by the monitoring IC 60 and the redundant IC 70, and each IC 60 is used. , 70 as a power supply terminal serving as a power supply source. The power supply terminal and the power supply terminal of the electrode pad 61 of the monitoring IC 60 are electrically connected by the bonding wire 90. The power supply terminal and the power supply terminal of the electrode pad 71 of the redundant IC 70 are electrically connected by the bonding wire 91. This configuration is adopted in order to reduce the number of electrode pads of the monitoring IC 60 and reduce the number of connections using bonding wires. Hereinafter, this effect will be described while comparing the present embodiment and related technologies.

  FIG. 4 shows a part of a semiconductor module according to related art. In FIG. 4, the same components as those shown in FIG. 3 are designated by the same reference numerals for convenience.

  As shown in FIG. 4, in the related art, the redundant IC 70 is attached to the monitoring IC 60 with the electrode pad 72 of the redundant IC 70 and the electrode pad 61 of the monitoring IC 60 facing in opposite directions with respect to the central portion of the redundant IC 70. Has been. In the configuration shown in FIG. 4, when the monitoring IC 60 is viewed from the monitoring front side surface 60b, the distance between the electrode pad 72 on the redundant front side surface 70b and the inner lead 80c1 as the power supply terminal is the configuration shown in FIG. Will be longer than. In this case, if the leads 80c as power supply terminals and the electrode pads 72 on the redundant front surface 70b are directly connected by one bonding wire, the bonding wire may be broken. In order to prevent breakage of the bonding wire, the lead 80c as a power supply terminal and the electrode pad 72 of the redundant front side surface 70b are connected in a state where the central portion of the bonding wire is largely curved in an arc shape in the thickness direction of the redundant IC 70. There is a need to. However, in this case, the bonding wire that largely warps in the thickness direction is sealed by the resin mold, and the dimension of the semiconductor module in the thickness direction increases.

  In order to avoid this problem, as shown in FIG. 4, a relay electrode pad 62 is formed on the monitoring front surface 60b of the monitoring IC 60. Then, the electrode pad 72 on the redundant front surface 70b and the relay electrode pad 62 are connected by the bonding wire 94, and the relay electrode pad 62 and the lead 80c1 as the power supply terminal are connected by the bonding wire 93. It is also possible to adopt it. However, in this configuration, it is necessary to additionally form the relay electrode pad 62 on the monitoring IC 60. Also, with this configuration, the number of operations for connecting the electrode pads with the bonding wire increases.

  Therefore, in this embodiment, the configuration shown in FIG. 3 is adopted. As a result, when the monitoring IC 60 is viewed from the monitoring front surface 60b, the distance between the electrode pad 71 on the redundant front surface 70b and the lead 80c1 as the power supply terminal can be made shorter than that shown in FIG. Therefore, the electrode pad 71 of the redundant IC 70 and the lead 80c1 as a power supply terminal can be directly connected by one bonding wire 91. As a result, it is not necessary to form the relay electrode pad 62 on the monitoring IC 60, and the number of electrode pads formed on the monitoring IC 60 can be reduced. In addition, it is possible to prevent an increase in the number of operations for connecting with the bonding wire.

  In FIG. 3, the bonding wire 92 is a wire connecting the DA converter 46 forming the monitoring IC 60 and the comparator 41 forming the redundant IC 70. Further, in FIG. 4, the bonding wire 95 corresponds to the bonding wire 92 in FIG.

  Returning to the description of FIG. 1 above, the voltage detection device includes a common power supply 50 which is a DC power supply, and a common communication line 51 which is a communication line connected to the common power supply 50. A common resistor 52, which is a resistor, is provided on the common communication line 51. In the common communication line 51, the individual communication line 53 connected to the signal output unit Ca of each of the monitoring units MD1 to MDn is connected to the opposite side of the common power source 50 across the common resistor 52.

  The control section 20 includes a signal input section Cb as a terminal, a first communication connection section T1 and a second communication connection section T2. On the other hand, the first to n-th monitoring units MD1 to MDn include a communication input unit TI and a communication output unit TO as terminals. In the present embodiment, the communication input unit TI and the communication output unit TO in each of the monitoring units MD1 to MDn are electrically connected to the monitoring IC 60.

  The control unit 20 and the first to nth monitoring units MD1 to MDn have a communication function. Between the first communication connection unit T1 of the control unit 20 and the communication input unit TI of the nth monitoring unit MDn, the communication output unit TO and the communication output unit TO of the m+1th monitoring unit MDm+1 (m=1, 2,..., N-1). The communication input unit TI of the m monitoring unit MDm, the communication output unit TO of the first monitoring unit MD1, and the second communication connection unit T2 of the control unit 20 are connected by a communication line CCL. That is, the control unit 20 and the monitoring ICs 60 of the first to nth monitoring units MD1 to MDn are connected in a daisy chain system.

  The terminal voltage of each battery cell as digital data detected by the main voltage detection unit 30 of each monitoring unit MD1 to MDn is input to the control unit 20 via the communication line CCL and the second communication connection unit T2.

  The control unit 20 performs a charge state determination process of determining whether or not there is a battery module in an overcharged state among the first to nth battery modules BM1 to BMn. Hereinafter, this process will be described.

  The control unit 20 first issues a command to close the first switch SW1 and open the second switch SW2 to the monitoring ICs 60 of the monitoring units MD1 to MDn via the first communication connection unit T1 and the communication line CCL. Output to. As a result, the first switch SW1 of each of the monitoring units MD1 to MDn is closed and the second switch SW2 is opened.

  Then, the control unit 20 determines whether or not there is a battery module in an overcharged state among the first to nth battery modules BM1 to BMn based on the input signal VM of the signal input unit Cb. The nth battery module BMn corresponding to the nth monitoring unit MDn will be described as an example. When the nth battery module is not in the overcharged state, the voltage is divided by the first voltage dividing resistor 40a and the second voltage dividing resistor 40b. The terminal voltage of the nth battery module BMn becomes lower than the reference voltage VREF output from the reference power supply 42. Therefore, the logic of the output signal of the comparator 41 is set to H, and no current flows from the communication power supply 43 to the output terminal side of the comparator 41 via the communication resistor 44 and the photodiode forming the photocoupler 45. As a result, the phototransistor forming the photocoupler 45 is opened, and no current flows from the common power supply 50 to the ground via the common communication line 51, the individual communication line 53, the signal output unit Ca, and the phototransistor. As a result, the logic of the input signal VM of the signal input unit Cb becomes H. When determining that the logic of the input signal VM of the signal input unit Cb is H, the control unit 20 determines that none of the first to nth battery modules BM1 to BMn is in the overcharged state.

  On the other hand, when the nth battery module is overcharged, the terminal voltage of the nth battery module BMn divided by the first voltage dividing resistor 40a and the second voltage dividing resistor 40b is output from the reference power supply 42. It becomes higher than the reference voltage VREF. Therefore, the logic of the output signal of the comparator 41 is set to L, and a current flows from the communication power supply 43 to the output terminal side of the comparator 41 via the communication resistor 44 and the photodiode forming the photocoupler 45. As a result, the phototransistor that constitutes the photocoupler 45 is switched from the open state to the closed state, and a current flows from the common power source 50 to the ground via the common communication line 51, the individual communication line 53, the signal output unit Ca, and the phototransistor. Flowing. As a result, the logic of the input signal VM of the signal input unit Cb is inverted from H to L. When determining that the logic of the input signal VM of the signal input unit Cb is L, the control unit 20 determines that at least one of the first to nth battery modules BM1 to BMn is in the overcharged state.

  Subsequently, the diagnostic process executed by the control unit 20 will be described.

  First, the diagnostic process of the reference power source 42 will be described with reference to FIG. This process is performed when the control unit 20 determines that a predetermined diagnosis execution condition is satisfied. Here, the diagnosis execution condition may be, for example, a condition that a predetermined time has elapsed since the previous diagnosis process was performed.

  In this series of processes, first, in step S10, an opening operation command for the first switch SW1 and a closing operation command for the second switch SW2 are output to each of the monitoring units MD1 to MDn. As a result, in each of the monitoring units MD1 to MDn, the first switch SW1 is opened and the second switch SW2 is closed.

  In a succeeding step S12, a command for changing the diagnostic voltage VT so as to cross the reference voltage VREF from below to above is output to the DA converter 46 of each of the monitoring units MD1 to MDn. Then, in step S14, it is determined whether or not the logic of the input signal VM of the signal input unit Cb is inverted from H to L before and after the diagnostic voltage VT is changed.

  When it is determined in step S14 that the logic of the input signal VM is inverted from H to L, the process proceeds to step S16, and it is determined that the reference power supply 42 has no abnormality. On the other hand, when it is determined in step S14 that the logic of the input signal VM is not inverted from H to L, the process proceeds to step S18 and it is determined that the reference power supply 42 is abnormal.

  When it is determined that the reference power supply 42 is abnormal, the control unit 20 may prohibit the voltage detection by the sub voltage detection unit.

  Subsequently, the diagnosis processing of the communication system from the comparator 41 to the signal input unit Cb via the photo coupler 45, the signal output unit Ca, the individual communication line 53, and the common communication line 51 will be described with reference to FIG. This process is performed when the control unit 20 determines that a predetermined diagnosis execution condition is satisfied. Here, the diagnosis execution condition may be, for example, a condition that a predetermined time has elapsed since the previous diagnosis process was performed.

  In this series of processes, after the process of step S10 is completed, the process proceeds to step S20, and a command to set the diagnostic voltage VT to a voltage lower than the reference voltage VREF is issued to the DA converter 46 of each monitoring unit MD1 to MDn. Output. Then, in step S22, it is determined whether or not the logic of the input signal VM of the signal input unit Cb is H.

  When it is determined in step S14 that the logic of the input signal VM is H, the process proceeds to step S24, and it is determined that no abnormality has occurred in the communication system. On the other hand, if it is determined in step S22 that the logic of the input signal VM is L, the process proceeds to step S26 and it is determined that an abnormality has occurred in the communication system.

  When the control unit 20 determines that an abnormality has occurred in the communication system, the control unit 20 may prohibit the voltage detection by the sub voltage detection unit.

  According to this embodiment described in detail above, the following effects can be obtained.

  (1) Each of the monitoring units MD1 to MDn includes a battery module via the main voltage detection unit 30, the first and fifth battery input units Ci1 and Ci5, the first battery input unit Ci1 and the fifth battery input unit Ci5. And a sub-voltage detector that detects the terminal voltages of BM1 to BMn. The sub-voltage detection unit includes resistors 40a and 40b for voltage division, a comparator 41, and a reference power supply 42. Since the sub-voltage detection unit is provided in each of the monitoring units MD1 to MDn, unlike the configuration in which the sub-voltage detection unit is provided in the control unit 20, a voltage input for electrically connecting each battery module and the control unit 20. It is not necessary to provide the control unit 20 with n units, which is the number of battery modules. Therefore, even if the number of battery modules changes due to a change in the specifications of the assembled battery 10, the control unit 20 that constitutes the voltage detection device can be shared.

  (2) The area of the monitoring front surface 60b of the monitoring IC 60 is larger than the area of the redundant back surface 70a of the redundant IC 70. Then, the redundant IC 70 was attached to the monitoring IC 60 with the entire surface of the redundant back side surface 70a being in contact with the monitoring front side surface 60b. Therefore, it is possible to suppress the distortion of the monitoring IC 60 on the entire surface of the redundant back side surface 70a. As a result, it is possible to prevent a decrease in the voltage detection accuracy of the main voltage detection unit 30.

  Furthermore, since the redundant IC is provided on the monitoring surface side 60b of the monitoring IC 60, the mounting area of each detection unit required when the main voltage detection unit 30 and the sub voltage detection unit are provided in each of the monitoring units MD1 to MDn can be reduced. As a result, it is possible to reduce the size of each of the monitoring units MD1 to MDn, which in turn can reduce the size of the voltage detection device.

  (3) A plurality of electrode pads 61 are formed along one side of the monitoring front side surface 60b, and a plurality of electrode pads 71 are formed along one side of the redundant front side surface 70b. Then, the redundant IC 70 was attached to the monitoring IC 60 with the electrode pad 71 of the redundant IC 70 and the electrode pad 61 of the monitoring IC 60 facing in the same direction or substantially the same direction. With this configuration, when the monitoring IC 60 is viewed from the monitoring front surface 60b, the distance between the electrode pad 71 on the redundant front surface 70b and the lead 80c1 as the power supply terminal can be shortened. Therefore, each of the electrode pad 71 of the redundant IC 70 and the electrode pad 61 of the monitoring IC 60 can be directly connected to the common lead 80c1 by the bonding wire. As a result, the number of electrode pads formed on the monitoring IC 60 can be reduced, and an increase in the number of operations for connecting with the bonding wire can be prevented.

  (4) Each of the monitoring units MD1 to MDn includes the signal output unit Ca and the photo coupler 45. The voltage detection device also includes a common power supply 50 and a common resistor 52. The signal input unit Cb of the control unit 20 is electrically connected to the opposite ends of the common resistor 52 from the common power source 50. According to this configuration, even if the number of battery modules changes due to a change in the specification of the assembled battery 10, it is not necessary to change the number of signal input units Cb of the control unit 20. Therefore, even if the specification of the battery pack 10 is changed, the control unit 20 constituting the voltage detection device can be shared.

  It should be noted that this configuration is effective in reducing communication lines connecting the monitoring units MD1 to MDn and the control unit 20 when the battery modules are mounted in distant spaces in the vehicle. Here, the separated space in the vehicle includes, for example, a space located below the seat and a space located below the trunk room on the vehicle rear side.

  (5) The logic of the output signal of the comparator 41 is inverted when the voltage divided by the first and second voltage dividing resistors 40a and 40b crosses the reference voltage VREF from bottom to top. The output signal of the comparator 41 of each of the monitoring units MD1 to MDn is input to the signal input unit Cb via the photo coupler 45, the signal output unit Ca, the individual communication line 53, and the common communication line 51. Therefore, when the logic of the output signal of at least one comparator 41 among the monitoring units MD1 to MDn is inverted, the logic of the input signal VM of the signal input unit Cb is inverted. Therefore, the control unit 20 can determine the overcharged state of the battery module based on the input signal VM of the signal input unit Cb.

  Further, in this embodiment, the logic of the output signal of the comparator 41 is set to H until the voltage divided by the first and second voltage dividing resistors 40a and 40b crosses the reference voltage VREF from below to above. did. Therefore, it is possible to prevent the current from flowing through the photodiode of the photocoupler 45 until one of the battery modules is overcharged, and the power consumption of the voltage detection device can be reduced.

  (6) With the first switch SW1 in the open state and the second switch SW2 in the closed state, the control unit 20 sets the diagnostic voltage VT so as to cross the reference voltage VREF from bottom to top. Changed. When the control unit 20 determines that the logic of the input signal VM of the signal input unit Cb is not inverted when the diagnostic voltage VT is changed, the control unit 20 determines that the reference power supply 42 has an abnormality. This makes it possible to properly determine whether or not the reference power supply 42 has an abnormality, and prevent the voltage detection device from being continuously used when the reference power supply 42 has an abnormality.

  (7) The control unit 20 sets the diagnostic voltage VT to a voltage lower than the reference voltage VREF with the first switch SW1 in the open state and the second switch SW2 in the closed state. Then, when the control unit 20 determines that the logic of the input signal VM is L, it is determined that an abnormality has occurred in the communication system. Accordingly, it is possible to properly determine whether or not there is an abnormality in the communication system, and it is possible to prevent continuous use of the voltage detection device in the state where the communication system has an abnormality.

  (8) The DA converter 46 is provided in the monitoring IC 60. Therefore, it is not necessary to separately provide the redundant IC 70 with a DA converter for diagnosis. This can simplify the circuit for diagnosis.

(Second embodiment)
Hereinafter, the second embodiment will be described with reference to the drawings, focusing on the differences from the first embodiment. In the present embodiment, as shown in FIG. 7, the main voltage detection unit 30, the DA converter 46, and the second switch SW2 are configured as a monitoring IC 60 that is one integrated circuit. That is, the first switch SW1 and the voltage dividing resistors 40a and 40b do not form the monitoring IC 60. On the other hand, the first switch SW1, the first voltage dividing resistor 40a, the second voltage dividing resistor 40b, the comparator 41, and the reference power supply 42 are configured as a redundant IC 70 that is one integrated circuit. In FIG. 7, the same components as those shown in FIG. 1 are designated by the same reference numerals for convenience.

  Incidentally, in the present embodiment, the first switch SW1 may be opened/closed by the main voltage detection unit 30 that receives a command from the control unit 20, for example.

  Also according to the present embodiment described above, the same effect as that of the first embodiment can be obtained.

(Other embodiments)
The above embodiments may be modified and implemented as follows.

  The arrangement method of the monitoring IC 60 and the redundant IC 70 is not limited to the method shown in FIGS. 2 and 3 above. For example, as shown in FIG. 8, each of the monitoring IC 60 and the redundant IC 70 is mounted on the die pad 80a and arranged side by side in the resin mold when the monitoring IC 60 is viewed from the monitoring surface side 60b. It may be. In FIG. 8, the same components as those shown in FIGS. 2 and 3 are designated by the same reference numerals for convenience.

  The monitoring IC 60 and the redundant IC 70 are not limited to those configured as separate integrated circuits. For example, in the first embodiment, the main voltage detection unit 30, the first switch SW1, the first voltage dividing resistor 40a, the second voltage dividing resistor 40b, the DA converter 46, the second switch SW2, the comparator 41 and the reference. The power supplies 42 are configured as the same integrated circuit. Then, in the same integrated circuit, a group of the main voltage detection unit 30, the first switch SW1, the first voltage dividing resistor 40a, the second voltage dividing resistor 40b, the DA converter 46, and the second switch SW2, and the comparator 41. And the group of reference power sources 42 are separated.

  In the first embodiment, as an insulating element that electrically insulates between the output terminal of the comparator 41 and the signal output unit Ca, and transmits a signal between the output terminal of the comparator 41 and the signal output unit Ca, Although the photocoupler 45 as the optical insulation element is used, it is not limited to this. For example, another insulating element such as a magnetic coupler as a magnetic insulating element may be used.

  As the charging state determination process executed by the control unit 20, a process of determining whether or not there is a battery module in an overdischarged state among the first to nth battery modules BM1 to BMn may be performed. . In this case, the reference voltage VREF may be set to a value with which it can be determined that the battery module is in the overdischarged state. Specifically, for example, the reference voltage VREF may be set to a value obtained by dividing the allowable lower limit value of the terminal voltage of the battery module by the first and second voltage dividing resistors 40a and 40b. In this setting, the reference power supply 42 may be connected to the inverting input terminal of the comparator 41, and the connection point of the voltage dividing resistors 40a and 40b may be connected to the non-inverting input terminal. According to this configuration, the voltage divided by the voltage dividing resistors 40a and 40b crosses the reference voltage VREF from above to below, whereby the logic of the output signal of the comparator 41 is inverted from H to L. Therefore, similarly to the determination of the overcharged state, the control unit 20 can determine that at least one battery module is in the overdischarged state based on the input signal VM of the signal input unit Cb.

  In this configuration, the diagnostic process shown in FIG. 5 can be performed. In this case, the process of step S12 may be changed to a process of changing the diagnostic voltage VT so as to cross the reference voltage VREF from above to below.

  Further, with this configuration, the diagnostic processing shown in FIG. 6 can be performed. In this case, the process of step S20 may be changed to a process of setting the diagnostic voltage VT to a voltage higher than the reference voltage VREF.

  In the first embodiment, the connection point of the first and second voltage dividing resistors 40a and 40b and one end of the second switch SW2 are connected to the non-inverting input terminal of the comparator 41, and the reference power source 42 is connected to the inverting input terminal. It may be connected. In this case, if the battery module is not overcharged, the logic of the output signal of the comparator 41 becomes L, and the photodiode of the photocoupler 45 becomes conductive.

  In the first embodiment, the output signal of the comparator 41 that constitutes the sub-voltage detection unit and the voltage detection value of the main voltage detection unit 30 are transmitted to the control unit 20 by using different communication systems. The configuration is not limited, and the same communication system may be used for transmission to the control unit 20. As this configuration, specifically, for example, the communication power supply 43, the communication resistor 44, the photocoupler 45, and the signal output unit Ca are removed from the monitoring units MD1 to MDn, and a communication line CCL that configures a daisy chain connection. The output signal of the comparator 41 may be transmitted to the control unit 20 using.

  -In the said 1st Embodiment, the control part 20 may perform the process which determines the abnormality of the 1st voltage division resistance 40a and the 2nd voltage division resistance 40b. This process is performed by, for example, the terminal voltage of the battery module converted from the respective battery cells 10a to 10d and the total value detected by the main voltage detection unit 30 and the divided voltage values of the first and second voltage dividing resistors 40a and 40b. If it is determined that there is a deviation, it may be determined that there is an abnormality in at least one of the first voltage dividing resistor 40a and the second voltage dividing resistor 40b.

  In the first embodiment described above, the area of the monitoring front surface 60b and the area of the redundant back surface 70a may be the same. Even in this case, the configuration of (2) of the first embodiment can be obtained.

  In the first embodiment, the redundant IC 70 is provided in the central portion of the monitoring IC 60, but the present invention is not limited to this. For example, the redundant IC 70 may be provided at a position displaced from the central portion of the monitoring IC 60.

  The main voltage detection unit is not limited to the one that individually detects the terminal voltage of each battery cell that constitutes the battery module, but the main voltage detection unit may be a serial connection body of a number of battery cells smaller than the number of battery cells that constitute the battery module. It may detect the terminal voltage. For example, in FIG. 1, the terminal voltage for each series connection of two battery cells in the battery module may be detected by the main voltage detection unit.

  -The number of battery cells constituting the battery module is not limited to four, and may be two, three, or five or more. Further, the number of battery cells forming the battery module does not have to be equal in each battery module.

  -The number of battery modules constituting the assembled battery 10 is not limited to a plurality, and may be one. In this case, for example, the voltage detection device may be provided with one monitoring unit.

  -The assembled battery is not limited to one including one series-connected body of a plurality of battery cells. For example, it may be an assembled battery in which a plurality of series-connected bodies of a plurality of battery cells are provided and the series-connected bodies are connected in parallel with each other.

  The first switch SW1 and the second switch SW2 are not limited to relays and may be, for example, N-channel MOSFETs, P-channel MOSFETs, analog switches or photorelays whose sources are connected to each other.

  Among the plurality of inner leads 80c1, the inner leads commonly used by the monitoring IC 60 and the redundant IC 70 are not limited to the power supply terminals of both the monitoring IC 60 and the redundant IC 70, but may be other terminals such as a common ground terminal. It may be.

  The battery cell may be, for example, a nickel hydrogen storage battery.

  DESCRIPTION OF SYMBOLS 10... Assembly battery, 10a-10d... 1st-4th battery cell, 20... Control part, 30... Main voltage detection part, 40a, 40b... 1st and 2nd voltage dividing resistor, 41... Comparator, 42... Standard Power supply, MD1 to MDn... First to nth monitoring section, Ci1 to Ci5... First to fifth battery input section.

Claims (8)

In a voltage detection device applied to an assembled battery (10) including a series connection body of a plurality of battery cells (10a to 10d),
A monitoring unit (MD1 to MDn) for detecting the state of the assembled battery;
A control unit (20) provided separately from the monitoring unit, the detection result of the monitoring unit being input;
A series connection body of at least two of the battery cells constituting the assembled battery is a detection block (BM1 to BMn),
Each of the battery cells forming the detection block, or a series connection body of the battery cells of a number smaller than the number of the battery cells forming the detection block in the detection block is a detection target battery,
The monitoring unit is
A main voltage detection unit (30) that detects the terminal voltage of each of the detection target batteries as the state of the assembled battery;
A positive electrode side input section (Ci5) electrically connected to the positive electrode side of the detection block;
A negative electrode side input portion (Ci1) electrically connected to the negative electrode side of the detection block;
A sub-voltage detection unit (40a, 40b, 41, 42) for detecting the terminal voltage of the detection block as the state of the assembled battery via the positive side input unit and the negative side input unit ,
The main voltage detection unit constitutes a monitoring IC (60) which is an integrated circuit having a flat rectangular parallelepiped shape in the thickness direction,
At least a part of the sub-voltage detection unit has a flat rectangular parallelepiped shape in the thickness direction and constitutes a redundant IC (70) which is an integrated circuit different from the monitoring IC,
In the monitoring IC, one of the two outer surfaces of which the thickness direction is the normal direction is the monitoring back side surface (60a), and the other surface is the monitoring front side surface (60b),
In the redundant IC, one of the two outer surfaces whose thickness direction is the normal direction is the redundant back side surface (70a), and the other surface is the redundant front side surface (70b),
The area of the monitoring front surface is set to be equal to or larger than the area of the redundant back surface,
The redundant back surface is mechanically connected to the monitoring front surface side in a state where the contour of the redundant IC does not protrude from the contour of the monitoring IC when the monitoring IC is viewed from the monitoring front surface side. Voltage detection device. The monitoring IC is mounted from the back side of the monitoring, and a lead frame (80) having a plurality of leads (80c1) around it is provided,
The area of the monitoring front surface is made larger than the area of the redundant back surface,
The monitoring IC has a plurality of electrode pads (61) formed along one side of the monitoring surface side in a region of the monitoring surface side that does not overlap with the redundant IC when the monitoring IC is viewed from the monitoring surface side. ) Has
The redundant IC has a plurality of electrode pads (71) formed on the redundant front surface along one side of the redundant front surface,
The redundant back side surface is mechanically connected to the monitoring front side surface with the electrode pad of the redundant IC and the electrode pad of the monitoring IC facing in the same direction or substantially the same direction,
Each of one of the electrode pads of the redundant IC and one of the electrode pads of the monitoring IC is bonded to a lead commonly used by the monitoring IC and the redundant IC among the plurality of leads. 91. The voltage detecting device according to claim 1 , which is electrically connected by 91). The number of detection blocks is plural,
The monitoring unit is provided individually corresponding to each of the detection blocks,
The sub-voltage detection unit,
A voltage dividing resistor (40a, 40b) which is a resistor for dividing the terminal voltage of the detection block,
A reference power source (42) that is a power source that outputs a reference voltage for detecting the state of charge of the detection block;
Including an inverting input terminal and a non-inverting input terminal, among the inverting input terminal and the non-inverting input terminal, the voltage divided by the voltage dividing resistor is input to one terminal and the reference voltage is input to the other terminal. An input comparator (41),
DC power supply (50),
A resistor (52) having a first end side connected to the DC power supply,
The monitoring unit is
A signal output section (Ca),
A communication switch (45) which is a switch that is closed or opened according to the logic of the output voltage of the output terminal of the comparator, and that electrically connects the signal output unit and the ground,
The second end side of the resistor is electrically connected to the signal output section of each monitoring section,
Wherein the control unit, the voltage detecting device according to claim 1 or 2 having electrically connected to the signal input portion (Cb) to the second end side of the resistor. In a voltage detection device applied to an assembled battery (10) including a series connection body of a plurality of battery cells (10a to 10d),
A monitoring unit (MD1 to MDn) for detecting the state of the assembled battery;
A control unit (20) provided separately from the monitoring unit, the detection result of the monitoring unit being input;
A series connection body of at least two of the battery cells constituting the assembled battery is a detection block (BM1 to BMn),
Each of the battery cells forming the detection block, or a series connection body of the battery cells of a number smaller than the number of the battery cells forming the detection block in the detection block is a detection target battery,
The monitoring unit is
A main voltage detection unit (30) that detects the terminal voltage of each of the detection target batteries as the state of the assembled battery;
A positive electrode side input section (Ci5) electrically connected to the positive electrode side of the detection block;
A negative electrode side input section (Ci1) electrically connected to the negative electrode side of the detection block;
A sub-voltage detection unit (40a, 40b, 41, 42) for detecting the terminal voltage of the detection block as the state of the assembled battery via the positive side input unit and the negative side input unit,
The number of detection blocks is plural,
The monitoring unit is provided individually corresponding to each of the detection blocks,
The sub-voltage detection unit,
A voltage dividing resistor (40a, 40b) which is a resistor for dividing the terminal voltage of the detection block,
A reference power source (42) that is a power source that outputs a reference voltage for detecting the state of charge of the detection block;
Including an inverting input terminal and a non-inverting input terminal, among the inverting input terminal and the non-inverting input terminal, the voltage divided by the voltage dividing resistor is input to one terminal and the reference voltage is input to the other terminal. An input comparator (41),
DC power supply (50),
A resistor (52) having a first end side connected to the DC power supply,
The monitoring unit is
A signal output section (Ca),
A communication switch (45) which is a switch that is closed or opened according to the logic of the output voltage of the output terminal of the comparator, and that electrically connects the signal output unit and the ground,
The second end side of the resistor is electrically connected to the signal output section of each monitoring section,
The said control part is a voltage detection apparatus which has a signal input part (Cb) electrically connected to the 2nd end side of the said resistor. The main voltage detection unit constitutes a monitoring IC (60) which is an integrated circuit having a flat rectangular parallelepiped shape in the thickness direction,
At least a part of the sub-voltage detection unit has a flat rectangular parallelepiped shape in the thickness direction, and constitutes a redundant IC (70) which is an integrated circuit different from the monitoring IC,
The voltage detection device according to claim 4 , wherein the monitoring IC and the redundant IC are arranged side by side in a plan view of the monitoring IC and the redundant IC. A voltage generator (46) for generating and outputting a diagnostic voltage,
The closed state electrically connects the detection block and the voltage dividing resistor to each other, and the open state electrically connects the detection block and the voltage dividing resistor to each other. A first switch (SW1) for shutting off
By being in the closed state, the voltage dividing input terminal which is one of the non-inverting input terminal and the inverting input terminal of the comparator to which the voltage divided by the voltage dividing resistor is input, A second switch (SW1) for electrically disconnecting the voltage dividing input terminal and the voltage generating unit by being electrically connected to the voltage generating unit and opened. ,
The control unit is
A process of operating the voltage generator to change the diagnostic voltage so as to cross the reference voltage, with the first switch being in the open state and the second switch being in the closed state; ,
When it is determined that the logic of the input signal of the signal input unit is inverted when the diagnostic voltage is changed, it is determined that no abnormality has occurred in the reference power supply, and the diagnostic voltage is changed. In that case, when it is determined that the logic of the input signal of the signal input unit is not inverted, a process of determining that an abnormality has occurred in the reference power supply is performed, and the voltage according to any one of claims 3 to 5. Detection device. A voltage generator (46) for generating and outputting a diagnostic voltage,
The closed state electrically connects the detection block and the voltage dividing resistor to each other, and the open state electrically connects the detection block and the voltage dividing resistor to each other. A first switch (SW1) for shutting off
By being in the closed state, the voltage dividing input terminal which is one of the non-inverting input terminal and the inverting input terminal of the comparator to which the voltage divided by the voltage dividing resistor is input, A second switch (SW1) for electrically disconnecting the voltage generation input terminal and the voltage generation unit by being electrically connected to the voltage generation unit and opened. ,
The control unit is
With the first switch in the open state and the second switch in the closed state, the diagnostic voltage should be lower than the reference voltage or the diagnostic voltage should be lower than the reference voltage. A process of operating the voltage generator to increase the voltage,
Based on the logic of the input signal of the signal input unit when the diagnostic voltage is made lower than the reference voltage or when the diagnostic voltage is made higher than the reference voltage, from the comparator to the communication The voltage detection device according to any one of claims 3 to 6 , which performs a process of diagnosing whether there is an abnormality in a communication system up to the signal input unit via a switch and the signal output unit.   The voltage detection device according to claim 6, wherein the voltage generation unit is provided in the main voltage detection unit.

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